Spark transmitter



Oct. 5, 1948. H. BENIOFF SPARK TRANSMITTER Filed Feb. 7, 1946 FIG.

INVENTOR HUGO BENIOFF Patented Oct. 5, 1948 UNITED STATES PATENT OFFICE SPARK TRANSMITTER Hugo Benioff, Pasadena, Calif., assignor, by

mesne assignments, to Submarine Signal Company, Boston, Mass, a corporation of Delaware Application February 7, 1946, Serial No. 646,080

7 Claims. 1

The present invention relates to an ultra high frequency electromagnetic transmitting device of the spark type and has for its purpose means for efiectively and efficiently radiating electromagnetic energy by means of a, spark circuit. The invention is an improvement on my copending application Serial No. 620,562 filed October 5, 1945.

In the present invention the antenna system iselectrically coupled with the oscillating circuit so that more or less the antenna oscillatory circuits and the oscillatory power supply circuit are independent of one another except for the coupling eifect. By this means it is possible to tune more sharply the supply circuit and thereby establish a more efl'lcient oscillatory circuit. In the arrangement of the present invention it will be noticed that the oscillatory supply or tank circuit has its spark electrodes arranged or placed in close proximity to the coupling loop of the antenna system.

The coupling loopis aligned in the direction of the sparking electrodes so that one end of the loop is close to the electrodes electrically while the other end is as far away as possible. The plates forming the capacitor for the tank circuit each have a sector cut away in which the loop of the antenna circuit is placed. It will also be noticed that in the present system the entire tank circuit is sealed fromthe atmosphere and the impulse transformer, which is contained within an evacuated casing, is positioned so that the conductor from one electrode may be extended to one of the sparking electrodes.

The invention will be more fully described in connection with the drawings illustrating an embodiment thereof in which Fig. 1 shows a vertical section through the invention and Fig.2 shows a horizontal section taken on the line 2 -2 of Fig. -1.

In the arrangement described in the figures the device is supported on a plate I to which a rear cover 2 is secured by means of a series of screws 3 passing through an outwardly extending flange of the cover into the plate. A dome 4, transparent to electromagnetic waves, is secured to the front of plate I by means of the screws 5 passing through a flange of the dome 4 into the plate I. Mounted within the dome 4 is the entire spark mechanism. For this purpose the plate I is provided with a large opening bordered by a thin flange 6 on which is retained the plate I by means of the clamping screws 8 passing through the plate from the top and the clamping ring 9 on the bottom side of the plate, both the plate and the ring resting in the shoulder forming the flange. The plate I is provided with a concentrically positioned annular recessed section I0 and within it an eccentrically positioned hole I'I just to one side of the center of the plate where the sparking electrodes I2 and The hole II is filled with an upwardly opening cup shaped member I4 of nonconductive material which is supported in the hole by means of a collar I5 extending upwardly from the plate I around'the edge of the hole II forming a hermetical seal between the cup and the plate.

The sparking electrodes I2 and I3 are positioned at the center of the capacitor plates I6 and II which, as indicated more clearly in Fig. 2, extend sectorially for about 240 in arc. The plates I6 and H are spaced close together with a mica separator I8 in between which has a perforation aligned with the electrodes I2 and I3. These plates I6 and I1 form the capacitor for the oscillatory circuit whichincludes the plates I6 and I1 and'the sparking electrodes I2 and I3. The thin annular section II) on the top plate at the edge of the top plate l6 terminates the effective capacity of the plate at this point. The lower plate I! is supported by three insulating projecting arms I9, 20 and 2I attached at the underside to the lower plate and supported to the outer portion of the upper plate 1 by means of the screws 22, with a separator block 23 for obtaining the proper spacing of the arms I9, 20 and 2I between the capacitor plates to provide the proper alignment. The mica plate I8 may be supported at the same time in this construction.

Within the cup I4 there is retained and supported the antenna system comprising the coupling loop member 24 which has a loopat the end the bottom portion 25 of which is directed radially towards the line joining the sparking electrodes I2 and I3. The upwardly extending arms of the loop, which actually forms a U- shaped section, are adjustably supported to the plate 26 at the top of the cup I4, the arms having an adjustable slot so that the position of the loop may be moved up and down with respect to the position of the electrodes and the capacitor plate.

The U-shaped loop 24 has outwardly extending arms 21 and 28, which are preferably capped by closed tubes 29 and 30 sliding over the arms 21 and 28 respectively so that the antenna length may be adjusted if desired.

A vacuum mounted impulse transformer 3| similarly as described in my aforementioned copending application Serial No. 620,562 is supported by the enclosed bowl or shell 32 in a her- I3 are positioned.

metical seal 33. The top end connection of the vacuum mounted impulse transformer leads directly to the conducting spring 34 and the electrode IS. The shell 32 is also sealed hermetically to the plate 1 so that the entire oscillatory circuit unit supported by the plate is a sealed unit which may be filled with gas if desired. In the operation-cf the: device; the capacitor .plates :al 6.

and I! are' -energized with the desired-'highfreq-uency impulses through the transformer to obtain a spark discharge across the electrodes l2 and i3 projecting slightly at the center; of the capacitor plates. The lower section of the loop 24 nearest the electrodes is coupled to the capacitor oscillatory circuit by the magnetic link ages of the arc and the nearer endof'thecon ducting loop 24. This induced-:currentacauses the v antenna circuit to be charged from which the electromagnetic energy is radiated. The construction in the present system permits the desired coupling betweencthe oscillatingtank cira cuit rand. the antennaecircuit and: provides a comprising an oscillatory circuit having a pair of opposed plates with discharge electrodes opposed to one another and anantenna system having an input loop one arm of which has a portion-ladjacent the discharge electrodes 2. An ultra high frequency--sparktransmitten comprising an oscillatorycircuit having a pair of' opposed plates with discharge electrodes opposed to one another and an antenna system having an inputloopwaligned with the discharge electrodeswith one side of the loop adjacent said electrodes.

3. An ultra high-frequency spark transmitter comprising anoscillatory circu-it'having a pair of opposed plates formed as segments of a disc; an-

antenna system having a- U-shaped loop lying substantially in a planeanddirected radially from the center ofsaid segments and a pair of discharge electrodes extending from the opposed discs towards one another segments.

4. An 'ultra high frequency spark transmitter.

comprising an oscillatorygcircuit havinga pair ofopposed plates formed assegments of a disc,

The present deviceat the center of. said.

an insulating separator positioned between said discs, an antenna system having a U-shaped loop lying substantially in a plane and directed radially from the center of said segments and a pair of discharge electrodes extending from the opposed discs towards one another at the center of said segments.

5. .ultra high; frequency. sparkv transmitter comprising an oscillatory circuit having a pair of opposed plates formed as segments of a disc with discharge electrodes extending towards one another from the center of said segments, means sealing said plates and electrodes from the externalpatmosphereincluding a cup shaped insulating membersealed to one of said segments andpositloned near the center thereof, a doublet antennahavingav U.-shaped loop extending into said cup aligned radially with said electrodes for coupling to said oscillatory circuit.

6. An ultra high frequency spark transmitter comprisinga plate memberhavi-ng :formed therein a bossed, segment. of; a disc, agsimilar, segment. supported inopposedrrelation thereto, azpair off electrodesw-extending-:towards: one. another. from; thecenter .of said segments, an: insulatingsepe arator between: saidsegments and a ..U -.shaped antenna coupling ,member aligned radially with. the sparking electrodes.

7. An ultra high frequencyxspark=transmitter comprising a plate member having formed therein a ,bossed segment of a disc, asimi-lar segment supported in opposed relation thereto; a pair-10f r electrodes extending .towards one: anotherwfrom the: center. of said .isegments, an; insulating sep-' arator. between saidzsegments and a U'-shaped antenna coupling member. aligned radially withthe-sparking-electrodes;:a cup shaped insulating memberpositioned'in the angular space betweentheredges of said. segments near ,thesparkingelectrodes and supporting therein said :U -shaped coupling member.

HUGO BENIOFF;

REFERENCES Q CITED. 3

The following references are of:.record in the. fileof thispatent:

UNITED STATES PATENTS Number Name Date 833,034 DeForest Oct. 9;1906. 1,217,483" Miller Feb. 27, 1917 2,240,941 Ohl- May 6, 1941.. 2,413,187 McCurdy'et a1. Dec. 24,1946" 

